WOW
What a can of worms I've opened up with this topic.
I am, however, inclined to side with Watto on this question, and just go for adding a small s to the Cooper's upper case S, so that more than one Cooper S becomes a pair, or group of Cooper Ss. I know it looks strange, but at least it doesn't upset those of us who like to see apostrophes used correctly.
... and to add to the growing list of pet peeves:
1. Unless you're referring to the "days of yore" in your text, "Your" is the possessive pronoun, and "You're" is the contraction of "you are".
2. Cars have "brakes", people take "breaks".
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Curly
'64 Cooper 'S' (Group Nb spec)
'67 Mini Marcos GT
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